How to set a correct heat curve?
Short answer:
Set the heat curve to the lowest possible value, but still having
comfortable room temperature.
The table shows some recommendations:
House with
radiators:
Needed flow temp.
when the outdoor
temp. is -10 °C:
Recommen-
ded heat curve
value:
Older than 20 years:
65 °C
1.4
Between 10 and 20
years old:
60 °C
1.2
Rather new:
50 °C
0.8
Floor heating systems need, in general, a lower heat curve value
Technical answer:
In order to save energy, the flow temperature should be as low as
possible, but still considering a comfortable room temperature.
This means the heat curve slope should have a low value.
See the heat curve slope diagram.
Choose the desired flow temperature (vertical axis) for your heating
system at the expected lowest outdoor temperature (horizontal axis)
for your area. Pick the heat curve closest to the common point of
these two values.
Example: Desired flow temperature: 60 (°C) at outdoor temperature:
-10 (°C)
Result:
Heat curve slope value = 1.2 (mid-way between 1.4 and 1.0).
In general:
•
Smaller radiators in your heating system might require a higher
heat curve slope. (Example: Desired flow temperature 70 °C
resulting in heat curve = 1.5).
•
Floor heating systems require a lower heat curve slope. (Example:
Desired flow temperature 35 °C resulting in heat curve = 0.4).
•
Corrections of the heat curve slope should be done in small steps
when having outdoor temperatures below 0 °C; one step pr. day.
•
If required, adjust the heat curve in the six coordinate points.
•
Setting of the desired
room
temperature has an influence on the
desired flow temperature even if a room temperature sensor /
Remote Control Unit is not connected. An example: Increasing the
desired
room
temperature results in a higher flow temperature.
•
Typically, the desired
room
temperature should be adjusted when
having outdoor temperatures above 0 °C.
VI.GU.T2.02
© Danfoss | 2017.09 | 161
Operating Guide ECL Comfort 310, application A333
